Stapling mechanism



Nov. 1, 1955 5. TURRALL 2,722,000

STAPLING MECHANISM Filed Dec. 21, 1951 4 Sheets-Sheet 1 Nov. 1, 1955 e. TURRALL 2,722,000

STAPLING MECHANISM Filed Dec. 21, 1951 4 Sheets-Sheet 2 Nov. 1, 1955 ca. TURRALL 2,722,000

STAPLING MECHANISM Filed Dec. 21, 1951 4 Sheets-Sheet 3 JNVENTOR Nov. 1, 1955 G. TURRALL 2,722,000

STAPLING MECHANISM Filed Dec. 21, 1951 4 Sheets-Sheet 4 f/VVENTo R A77 NE? United States Patent STAPLING MECHANISM George Turrall, Wandsworth Common, London, England, assignor to R. Hoe & Co. Inc., New York, N. Y., a corporation of New York Application December 21, 1951, Serial No. 262,714

3 Claims. (Cl. 17)

This invention relates to stapling mechanism of the kind in which, while the mechanism and the plies to be stapled together are on continuous movement, a length of stapleforming wire is taken from a wire-feed, is bent into the familiar U shape and the staple thus formed is forced through the plies and the ends of its legs are turned-over or clenched.

In a common form of such mechanism especially as applied to a rotary printing machine where the plies are formed by webs or sheets, the length of wire is taken from the wire feed by small shoulders projecting beyond the periphery of a cylinder, and is carried along a staple-forming horn where it is bent into the familiar U shape with its base parallel with the axis of the cylinder. Due to the increasing speeds at which machines are required to operate, there is the danger that the heat generated in the wire while it is being forced along the horn will be such as to prevent the satisfactory operation of the mechanism.

The main object of this invention is to provide an improved mechanism which will avoid any such difficulty.

A further object is to provide a mechanism which shall be simple and have a minimum of moving parts.

The present invention consists, broadly stated, in a cylinder having a staple-forming recess in its periphery,- a second cylinder having a staple-forming punch at its periphery to cooperate with the recess to force a length of staple-forming wire into the recess to form a staple, and on the first cylinder, at staple-driving plunger to eject the formed staple from the recess and to force its legs through the plies to be staple. The mechanism also includes a device by which a length of wire is taken from a wire feed and positioned to be engaged by the stapleforming punch and forced by it into the recess as the cylinders rotate in unison.

With such an arrangement the length of wire taken from the wire feed is not required to be forced along a horn and the staple is quickly formed by cooperation between the recess and the punch. The formed staple is then within the first cylinder and is carried around with it without frictional sliding contact until the staple inserting position is reached at which time the staple is forced from the cylinder by the driving plunger, the legs of the staple being forced through the plies and then turned-over by any usual clenching die on a third cylinder.

The invention is illustrated in the accompanying drawings in which Figure 1 is an end elevation and Figure 2 a plan view of Figure 1 of a complete stapling mechanism and of a part of a printing machine. Figures 3-7 are detail views to a larger scale, Figure 3 being a sectional elevation of the parts in the position in which a staple is formed, Figure 4 a view similar to Figure 3 but showing the parts in the position of inserting a formed staple,

Figures 5 and 6 are respectively a plan and a section to a still larger scale of the parts which cooperate to form a staple and Figure 7 is a detail local elevation of a cutting arrangement for the staple-forming wire.

Reference will first be made to Figures 1 and 2. In

ice

these figures the webs to be stapled together are indicated at W, these webs passing through the stapling mechanism indicated generally at S, thence between a cutting cylinder 1 and a cooperating gutter cylinder 2 which latter also constitutes a folding cylinder which operates to foldoff the severed and stapled products between folding-off rollers 3, 4. Such an operation of stapling, cutting and folding is widely used in printing mechanism and description is believed to be unnecessary except of the stapling mechanism S which forms the subject of this invention.

Considering this stapling mechanism S, it comprises three constantly rotating cylinders 5, 6 and 7. The cylinder 5 will be termed the punch cylinder, the cylinder 6 the holding cylinder and the cylinder 7 the die cylinder, the term cylinder being used in the manner which is common in the printing machine industry as meaning merely a rotating part;

The particular mechanism shown is formed to insert two staples in line across the width of the webs W (Figure 2) and as each stapling mechanism is identical the parts of both will be given the same reference numerals. Staple forming wire 8 is taken from a feed spool 9 by feed rollers 10, 11 which advance the end of the wire past a cutter 12 (Figure 7) to the periphery of the holding cylinder 6. The cylinder 6 carries a cutter operating member 12 which engages the cutter 12 as it passes, and severs a proper length of wire for a staple. Simultaneously with its severing the cut piece of wire is engaged by shoulders 28 which project from the cylinder 6 and is carried along in the space between the cylinder and a guide 13, past a staple forming position (Figure 3). While passing this position the length of wire is engaged by a staple-forming punch 14 on the punch cylinder 5 and this punch forces the wire into a staple-forming recess 15 in the holding cylinder 6. The base wall of this recess is formed by a staple-driving plunger 16 and this plunger or ejector is forced inwardly into the cylinder 6 by the punch. The formed staple is held within the cylinder 6 as it rotates from the staple-forming position to the staple driving position (Figure 4) in which it cooperates with the die cylinder 7. In this position the plunger 16 is ejected or moved radially outwards and forces the legs of the formed staple through the paper webs, a die 17 on the die cylinder 7 turning over the legs of the staple to complete the stapling operation. To complete the general description of the mechanism, by reference to Figures 1 and 2, the three cylinders 5, 6 and 7 are rotatable in side frames 18, 19 and are geared by gears 20, 21 and 22 to rotate together. The wire feed rollers 10, 11 are driven through gears 23 from a gear 24 on the holding cylinder 6, drive being transmitted from the gears 23 to the two sets of wire feeds by a shaft 25.

' More detailed description will now be given with reference to Figures 3-7. In Figures 3 and 4 the cooperating cylinders 5, 6 and 7 are shown separated from one another to enable the parts they carry to be more easily seen. Each punch 14 is provided with the necessary clearance on its upper and lower faces (as seen in Figure 3), and is carried at the end of a bolt 26 secured in the cylinder 5, and in operation enters the staple-forming recess 15, which is formed in a block 27 secured in the holding cylinder 6. The block 27 is formed with shoulders 28 that project outward from the block, as shown in Figures 3 and 4. As shown in Figure 5, two shoulders are located in axial alignment, one on each side of the recess 15, to engage the wire and carry it forward after it is cut to staple length.

The side walls of the staple forming recess are formed with radial grooves 29 extending inward from the shoulders 28. When the punch 14 is carried by rotation of its cylinder 5 into register with the recess 15 in the holding cylinder 6, the punch presses the wire into the recess to form the familiar U shape of staple as indicated at 30 in Figure 6, the limbs of the U being accommodated in the grooves 29 which position the staple radially.

In order to eject the formed staple when the recess 15 is carried round into register with the die 17 on the cylinder 7 (Figure 4), the plunger is formed with lugs 31 which at the stapling position engage fixed guides or cams 32 which are shaped to force the plunger 16 radially outwards. This action thrusts the legs of the formed staples 30 through the webs W and the die 17 turns over the legs.

The stapling mechanism being of particular value for effecting stapling at high speeds, the action of centrifugal force tending to move the plunger 16 outwardly after it ceases to be moved in by the punch 14 is resisted by providing additional cams or guides 33 below which the lugs 31 are carried by rotation of the cylinder 6 as the plunger is forced in, at the staple-forming position, by the punch 14. These other cams 33 are formed so as to permit the lugs 31 to be moved out by the cams 32 5 at the stapling position.

The cams or guides 32, 33 are conveniently formed in fixed cam blocks 34 which, as is shown in Figure 2, are disposed about the holding cylinder parts 6.

It is preferred to rotate the punch cylinder 5 at twice the angular speed of the holding cylinder 6, this being efiected of course by a suitable proportioning of the gears 21, 22 to reduce the contact-angle of the punch 14 and the recess 15. This will of course necessitate that a dummy recess (indicated at 15 in Figure 1) be provided in the cylinder 6.

As has been stated the plunger 16 would tend to be moved outwardly by centrifugal force and this action alone may be relied upon to eject the staple under the control of the earns 32. In any case the plunger 16 would have a limit to its outward movement, this limit being set so that the outer end of the plunger is positioned to take the length of wire. In the arrangement shown this outward limit is imposed by the end walls of the slots 35 (Figure 4) through which the lugs extend.

The arrangement shown in the drawings is intended to form and insert What is termed a transverse staple, i. e. a staple which is transverse to the length of the webs being stapled: the invention could of course be applied also to the formation and insertion of longitudinal staples, i. e. to staples which extend in a line with the length of the webs.

It may in some cases be desirable to form the plunger 16 in two parts divided along the line of the wire-receiving groove so that, at the wire feeding station, the wire is caused to snap into position between the two parts without however imposing such a holding force as would prevent the formed staple from being withdrawn from the plunger 16 in the subsequent inserting operation.

I claim:

1. In a rotary stapling mechanism for a printing machine, comprising a staple-holding cylinder having a recess with a staple-driving plunger movable therein, a punch cylinder having a solid punch fixed therein and arranged to force the said plunger backward into the recess to form a staple, wire feeding and cutting mechanism to supply wire of staple length to the staple holding cylinder, and in combination, a pair of fixed cams generally concentric with the periphery of the staple holding cylinder, and a pair of cam engaging members formed on the plunger for running engagement with the said plunger and in running engagement with the fixed cam's for intermittently reciprocating the said plunger and for holding it against reciprocation during periods between its reciprocating movements.

2. In a rotary stapling mechanism for a printing machine, comprising a staple-holding cylinder having a recess with a staple-driving plunger therein, a punch cylinder having a solid punch fixed therein and arranged to force the said plunger backward into the recess to form a staple, wire feeding and cutting mehanism to supply wire of staple length to the staple-holding cylinder, and in combination a cam held in fixed position at each side of the path of travel of the plunger, and cam engaging members integral with the said plunger and simultaneously engaging the cams for reciprocating the said plunger in time relation with the rotation of the staple-holding cylinder and the punch cylinder, to form and drive staples in products printed on the machine.

3. A stapling mechanism for a rotary printing machine and comprising a staple wire feeding and cutting device, a die cylinder and a cooperating staple holding cylinder having a recess slidably supporting a staple driving plunger adapted to take wire cut for a staple, and in combination a punch cylinder having a fixed punch projecting therefrom and operable to engage the staple driving plunger to force it into the recess and to form a staple, a pair of cam engaging members on the staple driving plunger, and a pair of arcuate cam members fixed in position in axial alignment with the staple holding cylinder for simultaneous engagement by the cam engaging members on the staple driving plunger, to drive the staple into a product and clench it against the die cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 945,506 Firm Jan. 4, 1910 955,505 Firm Apr. 19, 1910 2,026,135 Meyer Dec. 31, 1935 2,211,027 Quick et al. Aug. 13, 1940 2,224,743 Nolan Dec. 10, 1940 FOREIGN PATENTS 110,393 Australia Apr. 16, 1940 

